Today, thousands of people will converge on London to join in the Stop the War march. Among them may be readers of this newspaper, whose opposition to Anglo-American intervention in Iraq is based on moral objections, or on concern about the possible consequences for this country. Such scruples deserve respect. Most of the speakers who will set the tone for this march, though, have rather different motives, chief among them hostility to America. Those who are by no means anti-American, but who disapprove of George W. Bush, may find themselves uncomfortable in the company of those who see America as...